Samples of polyethylene (PE) and polytetrafluoro-ethylene (PTFE) materials exposed to simulated atomic oxygen (AO) exhibit mass erosion yields dependant upon their method of manufacture, density and surface finish. It is proposed that this is due to the internal chemical structure of the polymers for which a higher sample crystallinity results in a lower susceptibility to AO interaction. The manufacturing process of particular interest is that of ion beam sputter deposition, used in the production of thin films (20nm-1μm) of polymer materials for applications such as quartz crystal micro-balance (QCM) and silver film overlay devices. Additionally, changes in the "as supplied" material mass erosion yield and surface erosion morphology are caused by heat annealing processes and preparation of exposure surfaces by mechanical sectioning. These effects may be of concern when calculations of AO fluence are made using the mass loss technique, in which an accurate volume erosion yield for the test polymer is required. Experimental results also suggest that some improvement in AO resilience for an ion beam sputter deposited polymer may be achieved by reducing the rate of deposition.
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